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Objective.To determine risk factors and outcomes associated with ciprofloxacin resistance in clinical bacterial isolates from intensive care unit (ICU) patients.Design.Prospective cohort study.Setting.Twenty-bed medical-surgical ICU in a Canadian tertiary care teaching hospital.Patients.All patients admitted to the ICU with a stay of at least 72 hours between January 1 and December 31, 2003.Methods.Prospective surveillance to determine patient comorbidities, use of medical devices, nosocomial infections, use of antimicrobials, and outcomes. Characteristics of patients with a ciprofloxacin-resistant gram-negative bacterial organism were compared with characteristics of patients without these pathogens.Results.Ciprofloxacin-resistant organisms were recovered from 20 (6%) of 338 ICU patients, representing 38 (21%) of 178 nonduplicate isolates of gram-negative bacilli. Forty-nine percent ofPseudomonas aeruginosaisolates and 29% ofEscherichia coliisolates were resistant to ciprofloxacin. In a multivariate analysis, independent risk factors associated with the recovery of a ciprofloxacin-resistant organism included duration of prior treatment with ciprofloxacin (relative risk [RR], 1.15 per day [95% confidence interval {CI}, 1.08-1.23];P< .001), duration of prior treatment with levofloxacin (RR, 1.39 per day [95% CI, 1.01-1.91];P= .04), and length of hospital stay prior to ICU admission (RR, 1.02 per day [95% CI, 1.01-1.03];P= .005). Neither ICU mortality (15% of patients with a ciprofloxacin-resistant isolate vs 23% of patients with a ciprofloxacin-susceptible isolate;P= .58 ) nor in-hospital mortality (30% vs 34%;P= .81 ) were statistically significantly associated with ciprofloxacin resistance.Conclusions.ICU patients are at risk of developing infections due to ciprofloxacin-resistant organisms. Variables associated with ciprofloxacin resistance include prior use of fluoroquinolones and duration of hospitalization prior to ICU admission. Recognition of these risk factors may influence antibiotic treatment decisions.

Objective Communication regarding end-of-life care is frequently perceived as suboptimal, despite the intent of both health care providers and patients. We interviewed health care providers to determine their perspective regarding these barriers to communication. Materials and Methods Eleven focus groups with a total of 10 attending physicians, 24 residents, and 33 nurses were convened to explore barriers to end-of-life discussions on the Internal Medicine service at a 600-bed tertiary care hospital in Toronto, Canada. An interview schedule was designed to elicit information regarding the process of end-of-life discussions, barriers to these discussions, and possible interventions for limiting such barriers. Transcripts were qualitatively analyzed by 6 raters who independently identified “themes.” Themes were refined using the Delphi technique and classified under broader “categories.” Results Four main categories of barriers emerged, relating to (1) patients, (2) the health care system, (3) health care providers, and (4) the nature of this dialogue. Attending physicians and residents most frequently identified patient-related factors as barriers to discussions, followed by system, dialogue, and provider barriers (43%, 39%, 10%, and 8%, respectively, for attending physicians; 40%, 34%, 13%, and 13%, respectively, for residents). Nurses similarly identified patient-related and system barriers most frequently, but provider barriers were discussed more often than dialogue barriers (46%, 28%, 22%, and 4%, respectively). Conclusions Attending physicians, residents, and nurses perceive the recipients of their care, and the system within which they provide this care, to be the major source of barriers to communication regarding end-of-life care. This finding may impact on the effectiveness of quality-improvement initiatives in end-of-life care.

Nosocomial transmission of severe acute respiratory syndrome from critically ill patients to healthcare workers has been a prominent and worrisome feature of existing outbreaks. We have observed a greater risk of developing severe acute respiratory syndrome for physicians and nurses performing endotracheal intubation (relative risk [RR], 13.29; 95% confidence interval [CI], 2.99 to 59.04; p = 0.003). Nurses caring for patients receiving noninvasive positive-pressure ventilation may be at an increased risk (RR, 2.33; 95% CI, 0.25 to 21.76; p = 0.5), whereas nurses caring for patients receiving high-frequency oscillatory ventilation do not appear at an increased risk (RR, 0.74; 95% CI, 0.11 to 4.92; p = 0.6) compared with their respective reference cohorts. Specific infection control recommendations concerning the care of critically ill patients may help limit further nosocomial transmission.

We investigated the source of intravascular fat in systemic organs (brain, heart, and kidney) after massive pulmonary fat embolism during cemented arthroplasty. We used a bilateral cemented arthroplasty (BCA) in anesthetized mongrel dogs that simulates a cemented total-hip replacement procedure. We hypothesized that deformable fat globules could pass through the lung vasculature under high pulmonary artery pressure (Ppa). Using quantitative morphometry, we showed that the size of pulmonary vessel occluded by fat decreased from 12.8 +/- 15.2 microns 1 min after BCA to 4.9 +/- 5.1 microns at 120 min after BCA (p0.01). Ultrastructural studies demonstrated no evidence of acute inflammation around fat-occluded pulmonary vessels 3 h after BCA. Intravascular fat was found in all brain, heart, and kidney specimens examined 3 h after BCA (n = 6). No anesthetized animal in the "sham" (no BCA) group (n = 3) had intravascular fat at the same time period. Radiolabeled microspheres (15 microns diameter) did not reach the systemic circulation (1% nonentrapment) under the high Ppa after BCA. No patent foramen ovale was found in any dog at postmortem examination. We conclude that fat globules can traverse the pulmonary circulation within 3 h of orthopedic surgery. The difference between solid microspheres and fat in transpulmonary passage suggests that the composition, perhaps the deformability, of embolic material influences the lung's filtering capacity.

There have been few detailed, in-person interviews and examinations to obtain follow-up data on 5-year outcomes among survivors of the acute respiratory distress syndrome (ARDS).We evaluated 109 survivors of ARDS at 3, 6, and 12 months and at 2, 3, 4, and 5 years after discharge from the intensive care unit. At each visit, patients were interviewed and examined; underwent pulmonary-function tests, the 6-minute walk test, resting and exercise oximetry, chest imaging, and a quality-of-life evaluation; and reported their use of health care services.At 5 years, the median 6-minute walk distance was 436 m (76% of predicted distance) and the Physical Component Score on the Medical Outcomes Study 36-Item Short-Form Health Survey was 41 (mean norm score matched for age and sex, 50). With respect to this score, younger patients had a greater rate of recovery than older patients, but neither group returned to normal predicted levels of physical function at 5 years. Pulmonary function was normal to near-normal. A constellation of other physical and psychological problems developed or persisted in patients and family caregivers for up to 5 years. Patients with more coexisting illnesses incurred greater 5-year costs.Exercise limitation, physical and psychological sequelae, decreased physical quality of life, and increased costs and use of health care services are important legacies of severe lung injury.

A new technique of small group surgical teaching has been developed wherein the surgeon takes on the role of the patient. This technique, which incorporates extensive and immediate formative evaluation, has all the advantages of simulation techniques while avoiding the major problems of training, scheduling and cost. This method has been used to teach a wide variety of surgical disease processes with the major emphasis being teaching patient management strategies. Sixty-one medical students have been taught using this method and they have found it superior to conventional seminar teaching, particularly in the domains of problem solving, patient management strategies and thought provocation.

Little is known about the long-term outcomes and costs of survivors of acute respiratory distress syndrome (ARDS).To describe functional and quality of life outcomes, health care use, and costs of survivors of ARDS 2 yr after intensive care unit (ICU) discharge.We recruited a cohort of ARDS survivors from four academic tertiary care ICUs in Toronto, Canada, and prospectively monitored them from ICU admission to 2 yr after ICU discharge.Clinical and functional outcomes, health care use, and direct medical costs.Eighty-five percent of patients with ARDS discharged from the ICU survived to 2 yr; overall 2-yr mortality was 49%. At 2 yr, survivors continued to have exercise limitation although 65% had returned to work. There was no statistically significant improvement in health-related quality of life as measured by Short-Form General Health Survey between 1 and 2 yr, although there was a trend toward better physical role at 2 yr (p = 0.0586). Apart from emotional role and mental health, all other domains remained below that of the normal population. From ICU admission to 2 yr after ICU discharge, the largest portion of health care costs for a survivor of ARDS was the initial hospital stay, with ICU costs accounting for 76% of these costs. After the initial hospital stay, health care costs were related to hospital readmissions and inpatient rehabilitation.Survivors of ARDS continued to have functional impairment and compromised health-related quality of life 2 yr after discharge from the ICU. Health care use and costs after the initial hospitalization were driven by hospital readmissions and inpatient rehabilitation.

As more patients survive the acute respiratory distress syndrome, an understanding of the long-term outcomes of this condition is needed.We evaluated 109 survivors of the acute respiratory distress syndrome 3, 6, and 12 months after discharge from the intensive care unit. At each visit, patients were interviewed and underwent a physical examination, pulmonary-function testing, a six-minute-walk test, and a quality-of-life evaluation.Patients who survived the acute respiratory distress syndrome were young (median age, 45 years) and severely ill (median Acute Physiology, Age, and Chronic Health Evaluation score, 23) and had a long stay in the intensive care unit (median, 25 days). Patients had lost 18 percent of their base-line body weight by the time they were discharged from the intensive care unit and stated that muscle weakness and fatigue were the reasons for their functional limitation. Lung volume and spirometric measurements were normal by 6 months, but carbon monoxide diffusion capacity remained low throughout the 12-month follow-up. No patients required supplemental oxygen at 12 months, but 6 percent of patients had arterial oxygen saturation values below 88 percent during exercise. The median score for the physical role domain of the Medical Outcomes Study 36-item Short-Form General Health Survey (a health-related quality-of-life measure) increased from 0 at 3 months to 25 at 12 months (score in the normal population, 84). The distance walked in six minutes increased from a median of 281 m at 3 months to 422 m at 12 months; all values were lower than predicted. The absence of systemic corticosteroid treatment, the absence of illness acquired during the intensive care unit stay, and rapid resolution of lung injury and multiorgan dysfunction were associated with better functional status during the one-year follow-up.Survivors of the acute respiratory distress syndrome have persistent functional disability one year after discharge from the intensive care unit. Most patients have extrapulmonary conditions, with muscle wasting and weakness being most prominent.

To determine the correlation between global ratings and criterion-based checklist scores, and inter-rater reliability of global ratings and criterion-based checklist scores, in a performance assessment using an anesthesia simulator.All final-year medical students at the University of Toronto were invited to work through a 15-minute faculty-facilitated scenario using an anesthesia simulator. Students' performances were videotaped and analyzed by two faculty using a 25-point criterion-based checklist and a five-point global rating of competency (1 = clear failure, 5 = superior performance). Correlations between global ratings and checklist scores, as well as specific performance competencies (knowledge, technical skills, and judgment), were determined. Checklist and global scores were converted to percentages; means of the two marks were compared. Mean reliability of a single rater for both checklist and global ratings was determined.The correlation between checklist and global ratings was.74. Mean ratings of both checklist and global scores were low (58.67, SD = 14.96, and 57.08, SD = 24.27, respectively); these differences were not statistically significant. For a single rater, the mean reliability score across rater pairs for checklist scores was.77 (range.58-.93). Mean reliability score across rater pairs for global ratings was.62 (.40-.77). Global ratings correlated more highly with technical skills and judgment (r =.51 and r =.53, respectively) than with knowledge. (r =.24)Inter-rater reliability was higher for checklist scores than for global ratings; however, global ratings demonstrated acceptable inter-rater reliability and may be useful for competency assessment in performance assessments using simulators.

To examine the validity and reliability of performance assessment of undergraduate students using the anesthesia simulator as an evaluation tool.After ethics approval and informed consent, 135 final year medical students and 5 elective students participated in a videotaped simulator scenario with a Link-Med Patient Simulator (CAE-Link Corporation). Scenarios were based on published educational objectives of the undergraduate curriculum in anesthesia at the University of Toronto. During the simulator sessions, faculty followed a script guiding student interaction with the mannequin. Two faculty independently viewed and evaluated each videotaped performance with a 25-point criterion-based checklist. Means and standard deviations of simulator-based marks were determined and compared with clinical and written evaluations received during the rotation. Internal consistency of the evaluation protocol was determined using inter-item and item-total correlations and correlations of specific simulator items to existing methods of evaluation.Mean reliability estimates for single and average paired assessments were 0.77 and 0.86 respectively. Means of simulator scores were low and there was minimal correlation between the checklist and clinical marks (r = 0.13), checklist and written marks (r = 0.19) and clinical and written marks (r = 0.23). Inter-item and item-total correlations varied widely and correlation between simulator items and existing evaluation tools was low.Simulator checklist scoring demonstrated acceptable reliability. Low correlation between different methods of evaluation may reflect reliability problems with the written and clinical marks, or that different aspects are being tested. The performance assessment demonstrated low internal consistency and further work is required.

The development and maintenance of expertise in any domain requires extensive, sustained practice of the necessary skills. However, the quantity of time spent is not the only factor in achieving expertise; the quality of this time is at least as important. The development and maintenance of expertise requires extensive time dedicated specifically to the improvement of skills, an activity termed deliberate practise. Unfortunately, determining how to engage in this deliberate practise is not obvious for tasks such as diagnosis, which involve high stakes and are predominantly cognitive nature. Reflection on and adaptation of one’s cognitive processes is important; this could be supplanted by seeking out the opportunity to engage in trial and error in low risk environments such as simulators. Regardless, most individuals tend to favour well-entrenched activities and avoid practise. This may be due to lack of awareness of deficiencies in performance. However, it may also be due to the individual’s conception of the nature of expertise. Although expertise requires experience, experience alone is insufficient. Rather, the development of expertise is critically dependent on the individual making the most of that experience. As a result, motivational factors are fundamental to the development of expertise. Overcoming deficiencies in self-monitoring is not a sufficient remedy. It is also necessary is that clinicians form an attitude toward work that includes continual re-investment in improvement.

Haemodynamic changes during bilateral cemented arthroplasty (BCA) were compared in dogs anaesthetized with isoflurane/N2O (ISOF) or diazepam/fentanyl (100 microg x kg(-1))N2O(FENT). Eight animals were anaesthetized with each regimen. After establishing monitoring and recording baseline values, BCA was performed. Haemodynamic measurements included aortic blood pressure (ABP), pulmonary artery pressure (PAP), right and left atrial pressures, and cardiac output. These were recorded at 30, 60, 180 and 300 sec after BCA. Lungs were removed and examined postmortem using quantitative morphometry. Groups demonstrated similar increases in PAP (ISOF 15 +/- 2 to 32 +/- 7, FENT 19 +/- 4 to 38 +/- 13; P0.05 between groups, P0.05 vs baseline). The proportion of lung vasculature occluded by fat was not different between groups (ISOF 9.63 +/- 3.38%, FENT 8.85 +/- 2.20%). Stroke volume decreased similarly in both groups (P0,05 between groups, P0.05 vs baseline). However, ABP decreased within one minute of BCA in ISOF (111 +/- 17 to 55 +/- mmHg, P0.05 and two of eight dogs died. All FENT dogs survived and hypotension (118 +/- 20 to 102 +/- 24 mmHg) was transient and less severe (P0.05 vs ISOF). Increased heart rate (HR) was noted in FENT following BCA (73 +/- 8 to 108 +/- 25 beats x min(-1); P0.05). Baseline HR was higher in ISOF (P0.05) and no increase in HR was noted. Systemic vascular resistance decreased in ISOF (P0.05), but not FENT (P0.05 vs baseline, P0.05 vs ISOF). To assess the role of slower baseline HR in FENT (73 +/-8) versus ISOF (131 +/- 5), six FENT dogs were paced (130 beats x min(-1)) with epicardial leads and an AV sequential pulse generator to simulate the ISOF group's baseline HR. Haemodynamic stability was maintained in this group in spite of a more rapid baseline HR. The choice of anaesthetic regimen strongly influenced acute haemodynamic changes in response to BCA.

Survival analysis is a statistical method used to calculate the probability of an event such as death or relapse of disease occurring in a patient over time. Survival analysis is important in the interpretation of clinical research, and is frequently encountered in the colorectal literature. In this article, the terminology used in survival analysis is explained, specific examples are presented, and common methods of calculation demonstrated.